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The characteristics of winter weather condition in 2005 and its effect on the growth of winter wheat after winter are analyzed on the basis of the winter average air temperature and precipitation data of 2005 (December 2004 to February 2005) from 11 counties of Jining, through systemic analysis of the various growth phases of winter wheat. In the entire winter, air temperature was higher at first and became lower in the midand latewinter. The negative accumulated temperature was higher than normal, resulting in the freezing injury of wheat stem and consequently the increasing of seedling height, the decreasing of greenery area, and the increasing of stalk net weight and kilograin weight, so the average wheat yields in Jining were reduced. The relevant countermeasures and suggestions are proposed aiming at the main causes of wheat freezing damage.